Nobita's homework complaint becomes an actual window into how civilization builds itself, one messy tribe at a time. The film moves quietly through human history instead of rushing it, letting you sit with how fragile the first structures of society really are. Kids see the wonder of creation; adults recognize the weight of every choice that leads to the world they inherited. The vignette format means it rewards rewatching because you catch different layers depending on what you're looking for. It's Doraemon doing what it does best: using a gadget to ask a real question, then letting the characters live in the answer.

Nobita needs a topic for his summer vacation research homework. Blaming Adam and Eve's sin for the suffering their descendants endure, homework included, he gets a gadget from Doraemon that lets him observe the creation of the world and record it as a diary-style report. Suneo, Giant and Shizuka join in, and together they watch tribes and civilizations take shape. Meanwhile, the time patrol is hunting an illegal time machine, and its operators happen to overhear Giant talking about the genesis diary project. They capture Giant and Suneo, leaving Nobita, Shizuka and Doraemon to look after the genesis set and rescue their friends. The film is a comedic fantasy adventure.